Let me introduce You to the interresting story of the Friedrichshafen ff.49c of the tech-museum in Elsinore/Helsingør - DK:
This german plane was introduced very late in WW1 but achieved in the short time a name for reliability and ridgidness when on the water.
Hence it was attractive to several uprising airforces following the end end of war in 1918. Inbetween those, the Danish navy.
After few years some of the Danish ff.49's became mail-planes, wich the kingdom rich on Islands and the main parts of the country dividend by two sounds was in big need of. Later on this post-service slowly evolved to passenger transportation too.
Not a single ff.49 have survived today but at the tech-museum at Elsinore (Helsingør) they found that they had the six cylinder Benz engine used on the ff.49 in storage. Since plane-deals at that time was done by byuing one or several planes including the rights to build more self, the library of the Royal Danish Navy contained the drawings by wich the 'extras' was build. And with the engine and drawings in hand a handfull of volunteers started building what was the first plane of public transport in Denmark and is to become the only ff.49 in the world!
The work is steadily in progress, in the pace of two weekly build-evenings, but early on the builders ran into a unexpected problem: Nobody knows in wich colours the plane was painted at the time when the official Danish Company of airservice (DDL) was formed! There might be photos from that time but the actual colour and nuance isn't to determine out of a black/white photo and there might be persons who can tell, but their age alone would connect some doubth to the informations :-/
I find it tragi-comical that historians can tell so much of ancient civilisations and then a 95 year old colourscheme is not to find ;-)